Sag still the same with heavier spring at same preload
  • tmccarthy182
    Posts: 13
    Joined: Mon Oct 08, 2012 12:00 am

    Sag still the same with heavier spring at same preload

    by tmccarthy182 » Mon Sep 21, 2015 11:38 pm

    Hello,
    I have a question on shock springs. I have a 2007 CRF250R with the stock shock spring. I weight about 205 without gear. Before new fork springs, I bought a stock 2006 CRF450X rear shock spring (what the description was) on eBay to keep it affordable, and decided to install it since I got it quick. I looked it up and saw that the stock spring on the 06 450x is a 5.5 weight.

    I measured the length of the original stock spring on the shock before loosening the preload. I installed the new spring and tightened to the same preload to give myself a base.

    When I measured the sag on the new spring, it was exactly the same (about 120mm) as the original spring I had on.

    Did I get duped and purchase the same weight spring as my original, or am I missing something?

    Thank you for your help
  • mossman77
    Posts: 316
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    by mossman77 » Tue Sep 22, 2015 6:49 am

    Perhaps you have some stiction in the swing arm and/or shock linkage and the 0.3kg difference in spring rate isn't enough to see a noticeable difference. You could clean all your bearings really well and see if that makes a difference. Does it feel different? Any clue what rate is in the forks? Maybe they are too soft and the bike is teetering forward so that your bike is unbalanced and the rear sag isn't changing.
    2007 CRF250X
    2004 CRF230F (sold)
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    JimDirt
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    by JimDirt » Tue Sep 22, 2015 10:09 am

    I think your spring is too soft for your weight (you did not mention if your trail or track riding , and what your experience level is , so i am generalizing here) , you should have a 5.8 shock spring for your weight (stock is 5.2) , and the 0.46 will work if its all you have , and its definitely better than the stock 0.45 , its just not really enough for your weight , i would go with a 0.47 or 0.48 for the fork and 5.8 for the shock , and i think your numbers will be better and it will feel better , again this depends on your skill level and what type of riding your doing , as off road riding usually involves a backpack which adds more weight , so the rate would be higher than normal , and if your really fast (A or B Level) then the rate would be on the high side as well from normal for your weight

    And mossman77 is right , your bike may be unbalanced , even though you went stiffer in the front , the back (even when on a X) is too soft , i like to recommend a balanced spring set , so if its 0.48 fork , then it should be 5.8 shock , or if its 0.50 fork it should be a 6.0 shock , follow ?? , though there are exceptions , as i am bouncing between 205-215 , and i run a 5.8 rear but i run 0.52 in both my 450R and 450X for the forks , but i valved my suspension to work with this spring combo (kind of a Endurocross setup) though i am planning on going to a 6.0 shock spring , which will actually work better , but either way , the stock 450X springs are too soft for your weight (i feel they are)

    Just search eBay and find yourself a stiffer shock and fork spring (you can get by with the 0.46 X fork spring , but its going to be pushing it as its only really designed for someone up to about 190 to really be efficient) , , but you need a 5.7 or 5.8 for the shock to be correct for your weight , and i think a 0.48 would be about right for the fork for you , but that is the only way your going to get your sag numbers correct

    What is your free sag ?? (the bike under its own weight on the ground)
    2020 CRF450R
    2006 CRF450X
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    Weiser , Idaho
  • mossman77
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    by mossman77 » Tue Sep 22, 2015 10:37 am

    as off road riding usually involves a backpack which adds more weight , so the rate would be higher than normal , and if your really fast (A or B Level) then the rate would be on the high side as well from normal for your weight


    Just to be sure I'm understanding you correctly, when you say the rate "would be higher than normal", you mean that you would want a rate higher than normal, correct? In other words, more weight/faster rider = stiffer spring rate.
    2007 CRF250X
    2004 CRF230F (sold)
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    JimDirt
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    by JimDirt » Tue Sep 22, 2015 12:05 pm

    Correct , a 185 lbs A Level rider can run a 5.0 fork and 5.8 shock and be sprung about right , where a 185 lbs novice or casual rider would run a 0.46/5.5 and be about right , when your faster you hit stuff "faster" and harder , you jump farther and land harder , and need the extra stiffness to make up for that difference in speed/skill from a slower rider of the same weight

    Go to a MX race , ask a A level rider what rate spring he uses , find another rider about the same weight but who is a C rider , and you will find the spring rate will be softer than the A rider , even though they are at the same track with the same obstacles ,now go find a novice or casual rider , and "IF" they know what rate they have , theirs will be much softer yet , even though they are the same weight , but they most likely will not be jumping or at least not clearing the same jumps the faster C or A riders are

    Make sense ??
    2020 CRF450R
    2006 CRF450X
    Image
    Weiser , Idaho
  • mossman77
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    by mossman77 » Tue Sep 22, 2015 12:45 pm

    Yes. Thanks.
    2007 CRF250X
    2004 CRF230F (sold)
  • tmccarthy182
    Posts: 13
    Joined: Mon Oct 08, 2012 12:00 am

    by tmccarthy182 » Tue Sep 22, 2015 3:36 pm

    This is good stuff, thanks! I didn't realize how much heavier of springs I needed. I am a novice/almost intermediate rider, a mix of track and trail/ off road.
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    JimDirt
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    by JimDirt » Tue Sep 22, 2015 8:20 pm

    Go with a 0.48/5.8 , and i think you will get your sag numbers where you need them , and the ride will feel much better (it will actually feel plusher not stiffer once you have the correct/stiffer springs for your weight/skill)
    2020 CRF450R
    2006 CRF450X
    Image
    Weiser , Idaho
  • mossman77
    Posts: 316
    Joined: Tue Jan 13, 2015 9:28 am

    by mossman77 » Wed Sep 23, 2015 7:10 am

    For reference, I'm an advanced beginner and weigh 215 without gear. I just swapped the stock springs with 0.49/5.9 rates and it feels so much better. It has made me more confident in the bike and thus a better rider. Plus my arms don't get worn out so quickly so I can ride longer. 0.48/5.8 sounds perfect for you.
    Last edited by mossman77 on Wed Sep 23, 2015 11:36 am, edited 2 times in total.
    2007 CRF250X
    2004 CRF230F (sold)
  • tmccarthy182
    Posts: 13
    Joined: Mon Oct 08, 2012 12:00 am

    by tmccarthy182 » Wed Sep 23, 2015 9:05 am

    I will order those springs. Thanks for the help guys!
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    JimDirt
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    by JimDirt » Wed Sep 23, 2015 11:22 am

    No problem , glad to help !! ;)
    2020 CRF450R
    2006 CRF450X
    Image
    Weiser , Idaho
  • tmccarthy182
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    Joined: Mon Oct 08, 2012 12:00 am

    by tmccarthy182 » Thu Sep 24, 2015 8:06 am

    Been on insanity workout, at 200 now ;). Stuff works



    Meant to also ask, do I change the amount of oil in the fork with the heavier springs?
  • tmccarthy182
    Posts: 13
    Joined: Mon Oct 08, 2012 12:00 am

    by tmccarthy182 » Thu Sep 24, 2015 12:39 pm

    To add. The local suspension guys I've found only have 5.7 or 5.9 rear springs. They have the .48 fork springs. Would you suggest the 5.7 with a little more pre-load, or the 5.9? And would I need to change my fork springs to the level that I choose?

    I'd order the 5.8 online but I was going to do a race this weekend and needed them today or tomorrow morning.

    I appreciate your help
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    JimDirt
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    by JimDirt » Thu Sep 24, 2015 7:52 pm

    Sorry for not getting back sooner , i was at a Dr appointment today , it was 80 miles each way , so makes for a long day

    Anyway , the oil level is more of a ride and feel thing , if the bike bottoms too easily , then add some oil , but only add about 10cc at a time to each fork , you can do this thru the air bleed screw with a syringe , otherwise you have to remove the fork cap , which you can not do if the clamps are tight on the tube , so try to do this before you leave for the track if possible , stock my 450R calls for 402cc of oil in the forks , i run 380cc , but i also re-valved my suspension so the oil level is set to work with that , i run 380cc on both my 450R and 450X , if your valving is stock add what the manual says then go from there , but don't add too much , , stay within the 372cc to 413cc range for your bike

    As far as the springs go , since your needing it ASAP , go with the 5.9 rear , it will work with the 0.48 fork springs , if you notice the bike steers too quickly or knifes a little , then LOWER the forks in the clamps 2mm and that should help , but i think you will be fine with the 0.48/5.9

    Start your clickers out at 12 (12 out from just lightly seated) and adjust from there , do this during practice , do a lap or so , and click , then try again , if it feels worse then go the other way 2 clicks at a time , then dial in the final setting , you may have to adjust this as the day goes on , as the track will get rougher throughout the day , set the suspension so on the biggest jump , it might bottom or come close to it , but it should not bottom on every jump , just keep turning the compression clickers in 2 clicks at a time till the bike feels good under you , it should not dive into corners , and it should not push into or out of corners , set your rebound (forks) so the bike does not act darty , especially in whoops , set the rear rebound so the bike does not kick off jump faces , but does not pack under load from the whoops *packing would feel like you were going over bumps with the rear wheel locked up , it would slam to the next one and feel like the tire never left the ground*(the Rebound is the speed of the shock *or fork* shaft extending/rebounding , so if the bike bounces around , then you need to slow the speed down *softer*) , the high speed compression on the shock is for square edge holes and sharp edges , in other words the higher speeds of the shock shaft , not the physical speed of the bike , Low Speed Compression is for slower shock shaft speeds , that should get you thru the weekend

    Your stock base settings are

    FORKS:
    Compression: 8 clicks out(turn all the way in till lightly seated , then out (counterclockwise) from lightly seated
    Rebound: 9 clicks out from lightly seated

    SHOCK:
    High Speed Compression: 1 3/4 - 2 1/4 turns out from lightly seated
    Low Speed Compression: 9 clicks out from lightly seated
    Rebound: 7-10 clicks out from lightly seated
    2020 CRF450R
    2006 CRF450X
    Image
    Weiser , Idaho
  • FrankAllok
    Posts: 1
    Joined: Mon Mar 25, 2019 3:00 pm

    Sag still the same with heavier spring at same preload

    by FrankAllok » Sat Apr 06, 2019 4:23 am

    Ive go the bike up on the lift and went to adjust the preload to 8 turns... turned hard, but okay... lost count. Went back to no preload and now I cant budge it. The other side did the same thing.

    Right now they are both set at no preload and they aint turnin... and Mary has a lot of shlt...

    Does the bike have to be on the ground to adjust preload or what...

    Bad time for this to happen...

    Is there a wrench for these things...?

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